The invention relates generally to a method of forming brake shoes for vehicles and, in particular, to brake shoe ribs formed to be nested together to reduce the amount of material required in the manufacturing process.
In the prior art, brake shoe ribs were formed from a continuous strip of material which allowed for trim stock around each rib. The trim stock represented both additional material costs to the brake rib manufacturer, and additional processes for the trimming of the excess material from the brake shoe rib. Each rib was welded to a brake shoe table to which lining would be attached.
One prior art method for manufacturing a drum brake shoe is by forming a plurality of connected blanks from a strip of material. The plurality of blanks are each bent to form an arcuate outer surface with adjoining sides, and are cut individually from the remaining plurality of blanks. The blanks are trimmed to remove the excess material, and friction lining material is attached.
In another prior art method, a strip of shoe rim steel has holes punched into it, and a lining is molded to it in segments with a flat or curved top. The strip is then bent at locations between the lining segments so as to remain flat and not destroy the bond between the rim and the lining material. The assembly is trimmed to length, a web or rib is attached and the lining pads ground to a final dimension.